Portable data collection devices are widely used in manufacturing, service and package delivery industries to perform a variety of on-site data collection activities. Such portable data collection devices often include integrated bar code dataform readers adapted to read bar code dataforms affixed to products, product packaging and/or containers in warehouses, retail stores, shipping terminals, etc. for inventory control, tracking, production control and expediting, quality assurance and other purposes. Various bar code dataform readers have been proposed for portable data collection devices including laser scanners and one dimensional (1D) charge coupled device (CCD) imaging assemblies, both of which are capable of reading 1D bar code dataforms, that is, bar codes consisting of a single row of contrasting black bars and white spaces of varying widths. Both of these readers are also capable of reading a "stacked" two dimensional (2D) bar code dataforms such as PDF-417, which has row indicator patterns utilized by the reader for vertical synchronization.
A two dimensional (2D) imaging based dataform reader has been proposed in U.S. application Ser. No. 08/544,618, filed Oct. 18, 1995 and entitled "Extended Working Range Dataform Reader Including Fuzzy Logic Image Control Circuitry", now issued as U.S. Pat. No. 5,702,059 on Dec. 30, 1997. The 2D dataform reader disclosed in application Ser. No. 08/544,618, includes an imaging assembly having a two dimensional array of photosensors or photodiodes adapted to read 2D bar code dataforms (e.g., PDF-417, Supercode, etc.) with vertical synchronization row indicator patterns as well as matrix dataforms (e.g., MaxiCode, Data Matrix, Code 1, etc.) which do not include vertical synchronization patterns. The photosensors correspond to image pixels of a captured image frame and the terms "photosensors" and "pixels" will be used interchangeably. The 2D dataform reader disclosed in U.S. Pat. No. 5,703,059 utilizes an open loop feedback control system including fuzzy logic circuitry to determine proper exposure time and gain parameters for a camera assembly. U.S. Pat. No. 5,702,059 is incorporated in its entirety herein by reference.
While using a portable data collection device to sequentially read bar code dataforms affixed to products or containers in a production facility, warehouse or retail store, an operator may come upon an item which is damaged, incomplete, mislabeled, in the wrong location, etc. In such a event, it would be desirable for the operator to make a note of the problem item so that appropriate corrective action may be taken by supervisory personnel. However, requiring the operator to make a handwritten notation on a clipboard or input information concerning the item using a keyboard or keypad of the portable data collection device is both time consuming and error prone. What is needed is a portable data collection device having a 2D imaging assembly that can be actuated to read bar code dataforms by depressing a trigger and, when a problem item is found, the imaging assembly can be actuated with a separate trigger to record an image of the problem item. This would enable "information", that is, an image of the problem item, to be recorded without seriously interrupting the normal course of the operator's work. Additionally, it would be desirable to transmit the recorded image of the problem item to appropriate supervisory personnel so that appropriate corrective action may be taken. In certain instances, it may be sufficient to record a single frame of the image of a problem item, while in other cases, for example, if the item is larger than a field of view or target area of the imaging assembly, it may be necessary to record a continuous video image of the problem item to permit the operator to record a complete view of the item. It would also be desirable to provide an audio capture module to simultaneously capture the operator's voice, enabling the operator to provide further identification and/or commentary on the problem item to aid supervisory personnel in locating the item and taking appropriate corrective action.
Additionally, what is needed is a portable data collection device including an illumination assembly and a viewing assembly to assist the operator in properly aiming and positioning the portable data collection device with respect to a target object such that the target object is within a target area of the imaging assembly. A size of a target area of the imaging assembly is defined by a field of view of the imaging assembly and a distance between the imaging assembly and the target object. The target object may be a dataform to be read or an item to be imaged. Preferably the illumination assembly will include targeting optics which will project a "crosshair" shaped targeting beam of visible light corresponding to the field of view of the imaging assembly to aid an operator in aiming the device at the target object.
A viewing assembly would permit the operator to visualize the target area and the target object. Visualizing the target area of the image assembly would facilitate proper alignment of the target area and the target object thus insuring that the device is properly aimed. Further, visualizing the imaging target area and the target object would aid the operator in positioning the device relative to the target object such that the target object is encompassed within an outer perimeter of the target area.
Furthermore, in package delivery applications, upon delivery of a package, the delivery person typically uses a portable data collection device to read a bar code dataform affixed to the delivered package. Normally, the delivery person also obtains a signature of the person receiving the package. Typically, the signature of the person receiving the package is on a sheet of paper that must be filed with the package delivery records or on a signature capture digitizer pad so that the signature may electronically filed.
What is needed is a portable data collection device having a 2D imaging assembly that can be actuated to read a bar code dataform by depressing one trigger and can be actuated by a separate trigger, or applications software, to record an image of a signature of a person receiving a package so that the signature can be filed electronically.
As an alternative to using one trigger to read a bar code dataform and using the second trigger to image an adjacent signature block with a recipient's signature included therein a single trigger could be used to image and decode a dataform and capture an image of the recipient's signature. If the dataform includes encoded data regarding the position of the signature block with respect to the dataform, output data could include decoded dataform data and data representing the portion of the captured image corresponding to the signature block area. What is needed is a portable data collection device that can be actuated by a single trigger to capture an image of a bar code dataform and an adjacent signature block, decode the bar code dataform, determine the position of the signature block, and output a compressed digitized representation of the portion of the image comprising the signature block for subsequent downloading to a remote device.
What is also needed is an optic assembly for focusing an image of the target area onto a two dimensional photosensor array wherein the optic assembly includes a focusing module to permit the best focusing distance of the optic assembly to be changed by the operator manually or changed automatically in response to a signal representative of the sharpness of an image of a target area.